Changelog - sheets

All notable changes to sheets are documented in this file.

[2.0.0] - 2024-07-02

Added

New Utility Functions

• csv.filter(rows, predicate) - Filter rows based on predicate function
• csv.map(rows, transformer) - Transform rows using transformer function
• csv.merge(rows1, rows2) - Merge two CSV row sets
• csv.unique(rows, key_func) - Remove duplicate rows
• csv.sort(rows, comparator) - Sort rows using comparator function
• csv.transpose(rows) - Transpose CSV matrix (rows become columns)
• csv.group_by(rows, key_func) - Group rows by key function
• csv.column(rows, column_index) - Extract single column from rows

Enhanced Reader Class

• Reader:readall() - Get all remaining rows as array
• Reader:get(index) - Get specific row by 1-based index
• Reader:slice(start, finish) - Get slice of rows
• Reader:column(col_index) - Extract single column
• Reader:filter(predicate) - Filter rows
• Reader:map(transformer) - Transform rows

Enhanced DictReader Class

• DictReader:readall() - Get all remaining records as array
• DictReader:count() - Get record count
• DictReader:filter(predicate) - Filter records by predicate
• DictReader:map(transformer) - Map records with transformer
• BUG FIX: Fixed reset() method by properly tracking _consumed_header flag

Enhanced DictWriter Class

• DictWriter:writerows(dicts) - Write multiple records at once

Documentation

• Professional README_COMPLETE.md with full API reference
• CONTRIBUTING.md for developers
• Enhanced inline code comments
• Comprehensive test suite (test_csv_enhanced.lua)

Testing

• 25 comprehensive test cases in test_csv_enhanced.lua
• Tests for all new functions
• Edge case coverage
• Validation of bug fixes

Changed

• Version bumped from 0.1.0 to 2.0.0
• Enhanced error handling and validation throughout
• Improved DictReader implementation with proper state tracking
• Better documentation and examples

Fixed

• DictReader.reset() bug: The _consumed_header flag was not being set, causing reset to fail
• Improved null/empty field handling in DictReader
• Enhanced error messages for invalid parameters

Deprecated

• None

Removed

• None

Security

• None

[0.1.0] - 2024-06-01 (Initial Release)

Added

• Core CSV reader with row-based iteration
• Core CSV writer with row-based output
• DictReader class for dictionary-based reading
• DictWriter class for dictionary-based writing
• Dialect system with built-in presets (excel, excel_tab, unix)
• Support for custom dialects
• CSV format sniffer for auto-detection
• Test suite with basic coverage
• Basic examples

---

Version Guide

• v2.0.0 (2024-07-02): Major release with new features and bug fixes - Production ready
• v0.1.0 (2024-06-01): Initial release - Foundation version

Upgrade Notes

From 0.1.0 to 2.0.0

No breaking changes! Your existing code will continue to work.

New Capabilities

• Use new utility functions for data transformation
• Use new Reader methods for advanced queries
• Use new DictReader methods for filtering/mapping
• Benefit from bug fixes in reset() functionality

Recommended Updates

1. Update to v2.0.0 for bug fixes
2. Adopt new utility functions where applicable
3. Use new Reader/DictReader methods for cleaner code

Example of migration to new style:

-- Old way (still works)
local rows = csv.read_csv("file.csv")
local filtered = {}
for _, row in ipairs(rows) do
    if tonumber(row[2]) > 30 then
        table.insert(filtered, row)
    end
end

-- New way (cleaner)
local rows = csv.read_csv("file.csv")
local filtered = csv.filter(rows, function(row)
    return tonumber(row[2]) > 30
end)

Future Roadmap

Planned for v2.1.0

• Streaming support for large files
• More statistical functions
• Excel-specific features

Planned for v3.0.0

• Lua coroutine-based streaming
• Async I/O support
• Performance optimizations

---

Support

• For bug reports: Open an issue on GitHub
• For feature requests: Discuss in GitHub issues
• For help: Check README_COMPLETE.md and examples

License

MIT License - See LICENSE file for details